%I #13 Sep 07 2018 20:57:49
%S 0,2,3,4,4,5,5,6,6,6,6,7,7,7,7,8,8,8,9,8,8,8,10,9,8,9,9,9,11,9,12,10,
%T 9,10,9,10,13,11,10,10,14,10,15,10,10,12,16,11,10,10,11,11,17,11,10,
%U 11,12,13,18,11,19,14,11,12,11,11,20,12,13,11,21,12,22
%N Totally additive with a(prime(n)) = n + 1.
%H Andrew Howroyd, <a href="/A318994/b318994.txt">Table of n, a(n) for n = 1..10000</a>
%p a:= n-> add((1+numtheory[pi](i[1]))*i[2], i=ifactors(n)[2]):
%p seq(a(n), n=1..100); # _Alois P. Heinz_, Sep 07 2018
%t Table[Cases[If[n==1,{},FactorInteger[n]],{p_,k_}:>(PrimePi[p]+1)*k]//Total,{n,100}]
%o (PARI) a(n)={my(f=factor(n)); sum(i=1, #f~, my([p,e]=f[i,]); (primepi(p)+1)*e)} \\ _Andrew Howroyd_, Sep 07 2018
%Y Cf. A000040, A001222, A003963, A056239, A275024, A299757, A302242, A302243, A318995.
%K nonn
%O 1,2
%A _Gus Wiseman_, Sep 07 2018
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